Ch 17 Vocab (Eye)

Front 1

Accommodation

Back 1

Normal adjustment of the eye to focus on objects from far to near. The ciliary body adjusts the lens and the pupil constricts. When the eye focuses from near to far, the blank body flattens the lens and the pupil dilates

Front 2

Anterior chamber

Back 2

Area behind the cornea and in the front of the lens and Iris. It contains aqueous humor

Front 3

Aqueous humor

Back 3

Fluid produced by the ciliary body and found in the anterior chamber.

Front 4

Biconvex

Back 4

Consisting of the two surfaces that are rounded, elevated, and curved evenly, like part of a sphere. The lens of the eye is a biconvex body

Front 5

Choroid

Back 5

Middle, vascular layer of the eye, between the retina and the sclera

Front 6

Ciliary body

Back 6

Structure surrounding the lens that connects the chroid and Iris. It contains ciliary muscles, which control the shape of the lens, and it secretes aqueous humor

Front 7

Cone

Back 7

Photoreceptor cell in the retina that transforms light energy into a nerve impulse. Cones are responsible for color and central vision

Front 8

Conjunctiva

Back 8

Delicate membrane lining the undersurface of the eyelids and covering the anterior eyeball

Front 9

Cornea

Back 9

Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball.

Front 10

Fovea centralis

Back 10

Tiny pit or depression in the retina that is the region of clearest vision

Front 11

Fundus of the eye

Back 11

Posterior, inner part of the eye

Front 12

Iris

Back 12

Pigmented, or colored, layer that opens and closes to allow more or less light into the eye. The central opening of the iris is the pupil

Front 13

Lens

Back 13

Transparent, biconvex body behind the pupil of the eye. It bends light rays to bring them into focus on the retina

Front 14

Macula

Back 14

Yellowish region on the retina lateral to and slightly below the optic disc. Contains the fovea centralis, which is the area of clearest vision

Front 15

Optic chiasm

Back 15

Point at which optic nerve fibers cross in the brain

Front 16

Optic disc

Back 16

Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light

Front 17

Optic nerve

Back 17

Cranial nerve carrying impulses from the retina to the brain

Front 18

Pupil

Back 18

Central opening of the eye, surrounded by the iris, through which light rays pass. It appears dark

Front 19

Refraction

Back 19

Bending of light rays by the cornea, lens, and fluids in the eye to bring the Rays into focus on the retina.

Front 20

Retina

Back 20

Light sensitive nerve cell layer of the back of the eye containing photoreceptor cells (rods and cones)

Front 21

Rod

Back 21

Photoreceptor cells of the retina essential for vision in dim light and for peripheral vision

Front 22

Sclera

Back 22

Tough, white outer coat of the eyeball

Front 23

Thalamus

Back 23

Relay center of the brain. Optic nerve fibers pass through the thalamus on their way to the cerebral cortex

Front 24

Vitreous humor

Back 24

Soft, jelly like material behind the lens in the vitreous chamber. Helps maintain the shape of the eyeball